As there can be found many kinds of animals and plants living in the sea, various organisms may often adhere to water-exposed articles and have adverse effects thereon. The adhesion of such harmful aquatic organisms will cause a decrease in the service speed and an increase in the fuel consumption of marine vessels, and a decrease in the carrying capacity of inlet channels of cooling water.
To control these adhering organisms, various antifouling agents such as cuprous oxide and some isothiazolone derivatives disclosed in U.S. Pat. No. 4,127,687 have hitherto been known; however, their efficacy is not sufficient.